Support for hot tops



June 21, 1932. E MESSLER 1,863,574

SUPPORT FOR HOT TOPS Filed July 31, 1931 INVENTOR 511W!) 7%Wivr PatentedJune 21, 1932 EUGENE L. MESSLER, OF PITTSBURGH, PENNSYLVANIA surronr FORnor 'rors Application filed July 31,

My invention relates to the mounting and use of hot tops on ingot moldsduring the teeming and solidification of ingots.

In order to obtain to the'fullest extent the heat-conserving advantagesof a hot top, and to avoid possibility of causing a hanging ingot, it isdesirable that a hot top,-which 1 has been initially supported on theupper edge of an ingot mold, be permitted to sink into the mold cavityduring solidification and contraction of the ingot.

My invention provides for the mounting and accurate positioning of thehot top during teeming; and for the spontaneous release of the hot topduring solidification of the ingot metal, so that it floats upon, andsinks with the contraction of, the ingot metal in the mold cavity. r

My invention further permits the use of hot tops of such simple contour,and such positioning with respect to theingot mold and its cavity, thatin the majority of instances the hot top is not gripped and cracked bythe contracting ingot metal.

In the accompanying drawing Figure I is a plan view showing a formofhot-top supporting structure for effecting my object; Figure II is aside elevation of the same, indicating the positioning of a hot verticalsectional view mold and through a hot on in accordance with ing theposition of the hot top immediately after teeming; Figure IVis a similarview showing'the position of the hot top in the ingot mold cavity afterthe hot top supporting means have disintegrated under the temperaturesexistent during and immediately through an ingot top mounted theremy1i1vent1on,showview of a slightly modified form of hot top supportingstructure; Figure VI is a side elevation of the same; Figure VII is afragmentary sectional viewon an enlarged scale, showing the details ofthe supporting structure, and illustrating the manner in which a hot topis supported thereon; and Figure VIII is a similar view illustrating adisintegration of the structure suflicient to release top withrespectthereto; Figure III is a after teeming; Figure V is a bottom plan1931. Serial No. 554,219.

the hot top to sink with the ingot metal in the mold cavity. r

Where occurring throughout the figures of the drawing, reference numeral1 represents an'ingot mold, and reference numeral 2 a hot top therefor.

According to my invention, I mount on support the hot top on theingot'mold by means which disintegrate spontaneously unm dertemperatures existing during and im- "3 mediately after teeming. It maynot be said that this disintegration is slow at such temperatures. Thesupporting structure is, however, of such nature thatthe' disintegra- Vtion is retarded. The supporting structure thus serves to. support thehot top in its mounted position for at least such time. as is requiredto fully teem the ingot. Shortly after teeming it spontaneouslydisintegrates I, to'release the hot top. '70

- As illustrated, the hot top supporting structure, designated generallyby reference numeral 3, comprises primarily a torus or flat ring l; Thisfiat ring lis so proportioned ,4 for the size of ingot mold with whichitjis" used, that the outer portion of its width 4a lies upon the upperedge, of theingot mold, and theinner portion 46 of its width extendshorizontally inward of the mold cavity.

This flat ring 4 is'of a material which go burns or otherwisedisintegrates under the temperatures encountered. If it is of lightgauge steel, the disintegration is by fusion. If, as preferred, it is offibre board, partial: lypreproofed by compression, orby the in-szsclusion of asbestos or other non-combustible material, thedisintegration is by combus-. tion. In either instancethe disintegrationis retarded in that it does not occur instantly uponsubjection of thering 4 to molten metaleo at its teeming temperature.

In assembly, the ring 4 is placed upon the upper edge of the ingot mold1, and a hot top 2 is placed upon the annular region 46 which extendsmold cavity. Desirably, weight is brought to bear upon the ring portion4a which lies upon the ingot mold, by placing suitable material, such asa ring of metal, on' this portion of the ring. I 1

horizontally inward of theta.

' The hot top 2 is drical contour, and has throughout its height anoverall diameter slightly less than the diameter of the upper region inthe mold cavity. When the ingot metal is teemed through the hot top andthe ingot mold cavity is filled with the metal, the temperature to whichthe ring is subjected causes its disintegration within a relativelybrief period of time. As the inner portionlb of the horizontal ring 4disintegrates under the teeming temperature, assisted by the weight ofthe hot top 2, the hot top is released. Because of the further fact thatits diameter is slightly less than the diameter of the ingot mold borein its upper region, the hot top is thus free to float upon the metal inthe mold cavity and to sink in the mold cavity with the metal as-itcontracts.

As the freedom of thehot top to sink, when released by disintegration ofring portion 4?), is limited only by the contraction of the metal, andthe contour of the mold cavity, there is little clamping action of themetal on the hot top. In-a relatively great percentage of teemings itis, therefore, possible to remove the hot top from the solidified ingotin condition for subsequent reuse. This is more particularly the casewhen multiple-piece hot tops are used.

It is highly desirable to attach to flat ring 4 two annuli, each ofwhich performs a twofold function, and which together define thedivision between outer ring portion 4a and inner ring portion 4?). Of'the two annuli, annulus 5 is in position perpendicular to the under faceof ring 4:. It is shown as attached to ring 4 by means of foot 511 ontheannulus and engaging the inner portion 4?) of the ring. 7

The annulus 5 serves to position the ring with respect to the ingot moldcavity, and also serves to prevent leakage ofmetal between the ring land the upper edge of the ingot mold during and immediately afterteeming. 1

Annulus 7 is attached to extend perpendicularly upward from ring 4 bymeans of an outwardly directed foot 7 a engaging the outer ring portion4a. Annulus 7 serves to position the hot top properly with respect tothe ingot mold cavity, and also prevents leakage of metal between thelower edge of hot top 2 and the upper face of flat ring 4. If multiplepiece hot tops are used, the an nulus 7 avoids the necessity of tightlywiring the pieces together. v

The modified supporting structure of Figures V and VI is designatedgenerally by reference numeral 8. The modification illustrated in thesefigures of the drawing resides only in the special contouring of thedepending annulus 8a to fit the special contour of the mold cavity. Theupwardly extending exteriorly of simple, cylinannulus 81) may be ofsimple contour to receive an annulus of similar contour.

It should be understood that the annuli of the supporting structure may,like the flat ring, be made either of slowly combustible material, asfor example a partially fireproofedfibre board, or may be made of amaterial which will otherwise disintegrate under the temperatureconditions, as for example thin gauge steel.

My manner of'supporting the hot top on the ingot mold is far moresatisfactory than the expedient of suspending hot tops, to be releasedafter the ingot metal has been teemed; or the expedient of insertingwedges or blocks beneath a ledge on the hot top, and removing the blocksorwedges to permit'the hot top to'sink after teeming.

According to-my invention, the sinking of the hot top after teeming isspontaneously effected during the propertime period after teeming;possibility of ingot metal leakage is eliminated; and further the hottop itself is not clamped bvthe metal as it solidifies so that in manyinstances the hot top remainsin condition suitable for subsequent reuse.

- It should be understood that throughout the specification and p by theterms ring and annulus tolimit these structural elements to acircularcontour. In accordance with the contour of the ingot mold andhot top they may be approximately rectangular, or of any other contourconforming to that of the ingot mold and hot top.

I claim as my invention: '1. Means for supporting a hot top on an ingotmold comprising a flat ring retardedly disintegratable at thetemperatures existing during the teeming and solidification of aningot,an annulus attached to the lower face of the ring intermediate itswidthto extend downwardly in a generally perpendicular directiontherefrom, said annulus being flexible to conform closely to the borewall of an ingot mold cavity to form with the flat ring a seal therein,and an annulus extending upwardly from the oppositeface of the ringintermediate its width and constituting a positioning elementsurrounding the hot top and in co-operation with the fiat ring forming aseal at the lower edge of the hot top.

2. Means for supporting a hot top on an ingot mold comprising a flatring retardedly disintegratable at the temperatures existing during theteeming and solidification of'an ingot, an annulus attached tothe lowerface of the ring intermediate its width to extend downwardly in agenerally perpendicular direction therefrom, said annulus beingflexibleto conform closely to the bore wall of an lngot mold cavity toform with the fiat ring a seal therein, and an annulus extendingupwardly from the opposite face of the ring constituting a positioningelement disposed claims I do notintend to hand.

y EUGENE L. MESSLER.

